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(Presumably) Apple engineer comment on Lightning AV adapter design

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Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#31

Post by Cushman »

bitcartel wrote: post #21
dmishe wrote: post #2

I think the main takeaway is that yes, lightning is future proof and can adapt to any output you want it to. I do wonder what's the reason for encode/decode cycle was in the first place though.

I think the main takeaway is, why pay for a $50 widget when a $5 cable will do the job? For the consumer who just wants to connect their device to a HDTV, it's crazy they have to pay 10x more just because they're in the Apple ecosystem and not Android. As for being future-proof, by the time some cool new A/V interface hits the market, and we've all updated our TVs, the Lightning devices of today will be in a museum.

Somebody has to pay the piper-- the hardware to transmit HDMI has to exist somewhere. With a smart adapter, only the people who need the feature have to pay for it.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#32

Post by dmishe »

revelation wrote: post #22
taligent wrote: post #10

Earlier quoted context omitted.

I might be really confused but why is Apple going to be in deeper trouble ? Surely the future will be H.265 content which will have better quality for the same bandwidth. And it's unlikely that people are going to be demanding a higher output resolution than 1080p from their mobile device for anytime soon.

Again, this is a connector from your mobile device to a display. Nobody has ever done any lossy compression on that pathway; both because you can drive simple circuits at frequencies high enough to have plenty of bandwidth and because it would actively destroy information (hence lossy). This is such a big problem because the video you are playing has already been lossy compressed (H.265) and it will most certainly no…

I think that if you have a 1080p source on your phone, it goes to tv as 1080 and without another compression step, it's only mirroring that reduces the resolution (which, for ipad mini, is less than 1080p btw) and introduces compression pass

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#33

Post by dmishe »

drewcrawford wrote: post #26
revelation wrote: post #3

Earlier quoted context omitted.

He doesn't say, but probably because they just don't have the bandwidth. And thats where all this future proof talk goes deaf. New interfaces will only have more bandwidth, thats the whole point. Meanwhile, Lightning still has the same bandwidth and theres still a considerable penalty in serializing any other interface. If they can't even do 1080p lossless right now, they are in much deeper trouble for the future.

> If they can't even do 1080p lossless right now, they are in much deeper trouble for the future. Let me try and shed some light on this mystery. Consider this rumor. Also, I am not an electrical engineer, so I may be talking out of my ass. As best as I can tell, Lightning is not (yet, anyway) a real protocol like Firewire, USB, etc. What it is so far is USB with a different connector and some negotiating chips. So w…

Yep, and the comment about them using already existent h264 support in hardware I think supports dry-run-fastest-to-deadline solution.

Re pins, I'm not EE either, but I don't get why people concern about number of pins so much, as I asked earlier in this thread, is there a relation between number of pins and bandwidth (well with physics involved there is _some_)?

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#34

Post by kryptiskt »

taligent wrote: post #20
revelation wrote: post #17

Earlier quoted context omitted.

This isn't streaming, its the last 50cm from your computer to your display. The 200 times more of data are already handled without a sweat by today's interfaces. Dual link DVI, from 1999, can already do more than 1080p.

Sorry but are you talking about the right connector here ? Lightning is for the iPod, iPhone and iPad. Of course dual link DVI et al can do more than 1080p. They are all huge. Apple's needs to support not just today's thin devices but those for the next decade (iWatch ?).

That's a red herring, the MHL standard does raw video over an USB connector. And it's a real thing, exists on phones today.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#35

Post by bitcartel »

taligent wrote: post #23
bitcartel wrote: post #21

Earlier quoted context omitted.

I think the main takeaway is, why pay for a $50 widget when a $5 cable will do the job? For the consumer who just wants to connect their device to a HDTV, it's crazy they have to pay 10x more just because they're in the Apple ecosystem and not Android. As for being future-proof, by the time some cool new A/V interface hits the market, and we've all updated our TVs, the Lightning devices of today will be in a museum.

You know you can buy Lightning cables off eBay for $5. And that the original dock connector first appeared in the iPod 3G nearly a decade ago. So yes today's devices will be in a museum. But the connector could still be in use in 2023 and beyond. Worth keeping in mind.

Yes, you can get a Lightning to USB cable for charging and syncing for $5, but to connect to a TV you need to get the Lightning AV adapter which costs $50.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#36

Post by glitch »

jacquesm wrote: post #16
glitch wrote: post #12

Earlier quoted context omitted.

So, you're saying bandwidth increase while maintaining backwards compatibility won't be possible through the Lightning interface? Surely, USB 1.0 to USB 2.0 demonstrated a counter-example to your statement.

Notice the 2.0 there?

Yes, and? Lightning 2.0. Sure. That doesn't mean the physical interface changes. That doesn't mean there isn't backwards compatibility. That doesn't mean there isn't forwards compatibility. "And thats where all this future proof talk goes deaf" argument made no statements to support itself. "Meanwhile, Lightning still has the same bandwidth" is like saying "Meanwhile, USB still has the same bandwidth with USB 2.0 as it did with USB 1.0". There will be higher bandwidth Lightning 2.0 peripherals with Lightning 2.0 devices; but Lightning 1.0 peripherals will still be compatible. The Lightning interface doesn't establish some sort of permanent bandwidth cap to its future backwards-compatible revisions.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#37

Post by taligent »

dmishe wrote: post #33
drewcrawford wrote: post #26

Earlier quoted context omitted.

> If they can't even do 1080p lossless right now, they are in much deeper trouble for the future. Let me try and shed some light on this mystery. Consider this rumor. Also, I am not an electrical engineer, so I may be talking out of my ass. As best as I can tell, Lightning is not (yet, anyway) a real protocol like Firewire, USB, etc. What it is so far is USB with a different connector and some negotiating chips. So w…

Yep, and the comment about them using already existent h264 support in hardware I think supports dry-run-fastest-to-deadline solution. Re pins, I'm not EE either, but I don't get why people concern about number of pins so much, as I asked earlier in this thread, is there a relation between number of pins and bandwidth (well with physics involved there is _some_)?

Why wouldn't they use H.264 and their existing hardware ?

Do you really think it makes more sense to decode H.264 on the device then re-encode it in another format and then decode that on the adapter ? Sounds slow, illogical and bound to introduce more artifacts.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#38

Post by glitch »

drewcrawford wrote: post #26
revelation wrote: post #3

Earlier quoted context omitted.

He doesn't say, but probably because they just don't have the bandwidth. And thats where all this future proof talk goes deaf. New interfaces will only have more bandwidth, thats the whole point. Meanwhile, Lightning still has the same bandwidth and theres still a considerable penalty in serializing any other interface. If they can't even do 1080p lossless right now, they are in much deeper trouble for the future.

> If they can't even do 1080p lossless right now, they are in much deeper trouble for the future. Let me try and shed some light on this mystery. Consider this rumor. Also, I am not an electrical engineer, so I may be talking out of my ass. As best as I can tell, Lightning is not (yet, anyway) a real protocol like Firewire, USB, etc. What it is so far is USB with a different connector and some negotiating chips. So w…

> Obviously they wanted an even number so you could plug it in every which way

How so? A center pin is still the center pin when you flip it around. Odd pin counts work fine.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#39

Post by dmishe »

taligent wrote: post #37
dmishe wrote: post #33

Earlier quoted context omitted.

Yep, and the comment about them using already existent h264 support in hardware I think supports dry-run-fastest-to-deadline solution. Re pins, I'm not EE either, but I don't get why people concern about number of pins so much, as I asked earlier in this thread, is there a relation between number of pins and bandwidth (well with physics involved there is _some_)?

Why wouldn't they use H.264 and their existing hardware ? Do you really think it makes more sense to decode H.264 on the device then re-encode it in another format and then decode that on the adapter ? Sounds slow, illogical and bound to introduce more artifacts.

Nope. This is _the_ question here, what prevented them from pushing framebuffer data to the adapter, which then puts it into HDMI compatible form

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#40

Post by glitch »

lunixbochs wrote: post #5
batgaijin wrote: post #4

Lightning is an Intel feature that Apple is trying to support right? I mean I can't tell if they firmly support this or if since Intel is there only chip supplier they are kind of bound to supporting this.

You're thinking about Thunderbolt?

Yes, he/she is thinking about Thunderbolt.
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